Natal dispersal and breeding dispersal of a subsocial spitting spider (Scytodes pallida) (Araneae: Scytodidae), from Singapore

Abstract

AbstractSocial spiders are thought to have evolved from subsocial ancestors, species in which siblings have an extended association with their parent, but disperse from the natal nests before reaching reproductive maturity. Therefore, natal dispersal is a factor that may constrain permanent socialization. Understanding the natal dispersal behaviour of subsocial species may provide insights into the sociality of spiders. In this study, we investigated the natal dispersal and breeding dispersal patterns in a subsocial spitting spider Scytodes pallida in Singapore. Spiderlings stayed in their natal nest for 2–3 weeks and then dispersed more or less in clusters, with a short mean travel distance of 218.9 cm. Those from natal nests that contained more spiderlings dispersed earlier and at a smaller body size. The mean distance dispersed significantly increased with the clutch size (the number of spiderlings in a nest). This suggests that competition for nest sites in the vicinity of the natal nest may affect dispersal distance. The results from observations of the breeding dispersal (nest relocation) show that significantly more juveniles than adults, more males than females and more non‐brooding (egg free) than brooding (egg carrying) females were likely to relocate their nests. Based on the results of the breeding dispersal, mate competition and inbreeding avoidance do influence the natal dispersal of spitting spiders.